Maf Comp vs Latency question
Jun 7, 2014, 06:13 AM
#31
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Merlin was talking about the radiator fan kicking on and blowing air across the cone filter which would screw up these values obviously. Just something to consider. Is your intake positioned in a way where that cooling fan would blow air across it? Although @ highway speeds I don't know if that would come into play as much.
Jun 7, 2014, 07:25 PM
#32
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Your air filter is no where near the radiator fan and its positioned perfectly to not be affected by incoming air flow negatively imho. Have you checked your maf scaling and compensation tables like I suggested and compared them to a stock version of your Rom yet?? I see the large metal pipe, which again if not scaled properly will cause all the issues you're having. Most tuners that I've talked to recommend the rubber/silicone style intake upgrade instead of a metal pipe because they cause less issues with scaling the maf.
Last edited by jrainwater; Jun 7, 2014 at 08:58 PM.
Jun 8, 2014, 09:44 AM
#34
Evolving Member
yeah the MAF scaling tables are all stock. I'm not exactly sure how the MAF scaling would change this though as the O2 feedback is centered around zero. It certainly seems like the MAF is picking up fluctuations in the incoming air even though the throttle etc are all constant. It fluctuates the same as if I were to be blipping the throttle a little (like cruising with a TPS of 25% and then blipping it to 30%).
Yea the catch cans are a little different internally, but I got the basic idea from that DIY catch can thread.
Yea the catch cans are a little different internally, but I got the basic idea from that DIY catch can thread.
Jun 9, 2014, 08:28 AM
#36
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yeah the MAF scaling tables are all stock. I'm not exactly sure how the MAF scaling would change this though as the O2 feedback is centered around zero. It certainly seems like the MAF is picking up fluctuations in the incoming air even though the throttle etc are all constant. It fluctuates the same as if I were to be blipping the throttle a little (like cruising with a TPS of 25% and then blipping it to 30%).
Yea the catch cans are a little different internally, but I got the basic idea from that DIY catch can thread.
Yea the catch cans are a little different internally, but I got the basic idea from that DIY catch can thread.
Jun 9, 2014, 09:24 AM
#37
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75.48
62.9
522.0700000000001
496.91
mean?
Jun 9, 2014, 12:44 PM
#39
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I assume he is telling us to leave the car in closed loop at higher load levels but random numbers don't really help us out. Nor am I interested in altering the vehicles natural open/closed loop load and rpm parameters either. I get the idea, but proper maf scaling would fix the issue without messing with when the car goes into open loop.
Jun 9, 2014, 09:32 PM
#40
Evolving Member
Read the advanced fuel thread linked below. They found that LTFT affected WOT fueling, and a fix was to lower the LT Closed Loop trim to 500hz.
https://www.evolutionm.net/forums/ec...l-options.html
https://www.evolutionm.net/forums/ec...l-options.html
Jun 9, 2014, 10:03 PM
#41
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The issue isn't happening at wot though. The whole thread is about the car swinging rich during low load cruise speeds on a non stock intake tube.
Jun 10, 2014, 03:28 AM
#42
As Mychailo mentioned, AFR should be swinging back and forth around 14.7:1. That is how closed-loop AFR control works with factory narrow band oxygen sensor.
Zeitronix seems to filter some of that swinging and shows rather "steady" 14.7:1 at the gauge, but AEM seems to show "unfiltered" numbers.
I think MAF signal becomes more "unstable" after putting hard intake pipes, and especially if it is too close to the MAF output, if possible, try to maintain enough straight silicon coupler section between the hard pipe and MAF housing.
I also got random rpm dipping and lean idle condition sometimes (especially when trying to move forward from dead stop then suddenly stops again with clutches in) after putting Cusco hard intake pipe, and playing with ECU settings help, but not fixed completely. (Thanks for your input about this jrainwater at another thread)
Zeitronix seems to filter some of that swinging and shows rather "steady" 14.7:1 at the gauge, but AEM seems to show "unfiltered" numbers.
I think MAF signal becomes more "unstable" after putting hard intake pipes, and especially if it is too close to the MAF output, if possible, try to maintain enough straight silicon coupler section between the hard pipe and MAF housing.
I also got random rpm dipping and lean idle condition sometimes (especially when trying to move forward from dead stop then suddenly stops again with clutches in) after putting Cusco hard intake pipe, and playing with ECU settings help, but not fixed completely. (Thanks for your input about this jrainwater at another thread)
Jun 10, 2014, 02:05 PM
#43
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I have heard that the "silicone" intakes that are molded for the Evo are way easier to tune, have the same positive effect the metal ones do, and are all around easier to work with. Can anyone confirm this with personal experience please??
